We recently reported on the remarkable story of a woman who has never felt pain before after 39 years — that sounds like a good deal to a lot of people, but it’s actually not.

In fact, the woman described it as a pleasant experience to feel pain for the first time when scientists gave her naloxone, a drug given to addicts, and then exposed her to a laser. The finding could have major implications for development of treatments to deal with pain. It’s a rare condition found in only a handful of people.

But there are tremendous downsides to not having pain. Many times people born with this condition gnaw off their fingertips or their lips — after all, they can’t feel any pain so they have no reason to stop what they’re doing.

The fact is, although pain is extremely unpleasant, it serves a hugely important purpose: it’s a signal that something is wrong and our bodies are being harmed. If you couldn’t feel pain, you wouldn’t know that your wisdom tooth was rotting and leading to an infection in your mouth. You wouldn’t know to immediately pull your hand off a hot pan as it was searing your skin. And you wouldn’t feel the need to go to the emergency room after a hard fall on your bike caused internal bleeding and broken bones.

Basically, pain is a signal that something is wrong, and you need to fix it right away. Without it, we wouldn’t last too long without damaging our bodies, potentially beyond repair.

This condition experienced by the woman is known as congenital insensitivity to pain (CIP), and it is a rare condition where people can’t feel physical pain.

Patients can still “feel” things with touch, and can sometimes detect changes in temperature, but the practical reality is that people with the condition tend to suffer from severe infections and corneal damage due to not detecting things in the eye. It can open one up to severe diseases.

There are two types of congenital pain indifference. There’s insensitivity, which means that a person cannot detect pain or describe its intensity, and then there’s indifference, were a person can feel the pain but doesn’t respond by getting away from the situation.